includes/resourceloader/ResourceLoader.php

   1 <?php
   2 /**
   3  * Base class for resource loading system.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @author Roan Kattouw
  22  * @author Trevor Parscal
  23  */
  24
  25 /**
  26  * Dynamic JavaScript and CSS resource loading system.
  27  *
  28  * Most of the documentation is on the MediaWiki documentation wiki starting at:
  29  *    https://www.mediawiki.org/wiki/ResourceLoader
  30  */
  31 class ResourceLoader {
  32         /** @var int */
  33         protected static $filterCacheVersion = 7;
  34
  35         /** @var bool */
  36         protected static $debugMode = null;
  37
  38         /**
  39          * Module name/ResourceLoaderModule object pairs
  40          * @var array
  41          */
  42         protected $modules = array();
  43
  44         /**
  45          * Associative array mapping module name to info associative array
  46          * @var array
  47          */
  48         protected $moduleInfos = array();
  49
  50         /** @var Config $config */
  51         private $config;
  52
  53         /**
  54          * Associative array mapping framework ids to a list of names of test suite modules
  55          * like array( 'qunit' => array( 'mediawiki.tests.qunit.suites', 'ext.foo.tests', .. ), .. )
  56          * @var array
  57          */
  58         protected $testModuleNames = array();
  59
  60         /**
  61          * E.g. array( 'source-id' => 'http://.../load.php' )
  62          * @var array
  63          */
  64         protected $sources = array();
  65
  66         /** @var bool */
  67         protected $hasErrors = false;
  68
  69         /**
  70          * Load information stored in the database about modules.
  71          *
  72          * This method grabs modules dependencies from the database and updates modules
  73          * objects.
  74          *
  75          * This is not inside the module code because it is much faster to
  76          * request all of the information at once than it is to have each module
  77          * requests its own information. This sacrifice of modularity yields a substantial
  78          * performance improvement.
  79          *
  80          * @param array $modules List of module names to preload information for
  81          * @param ResourceLoaderContext $context Context to load the information within
  82          */
  83         public function preloadModuleInfo( array $modules, ResourceLoaderContext $context ) {
  84                 if ( !count( $modules ) ) {
  85                         // Or else Database*::select() will explode, plus it's cheaper!
  86                         return;
  87                 }
  88                 $dbr = wfGetDB( DB_SLAVE );
  89                 $skin = $context->getSkin();
  90                 $lang = $context->getLanguage();
  91
  92                 // Get file dependency information
  93                 $res = $dbr->select( 'module_deps', array( 'md_module', 'md_deps' ), array(
  94                                 'md_module' => $modules,
  95                                 'md_skin' => $skin
  96                         ), __METHOD__
  97                 );
  98
  99                 // Set modules' dependencies
 100                 $modulesWithDeps = array();
 101                 foreach ( $res as $row ) {
 102                         $module = $this->getModule( $row->md_module );
 103                         if ( $module ) {
 104                                 $module->setFileDependencies( $skin, FormatJson::decode( $row->md_deps, true ) );
 105                                 $modulesWithDeps[] = $row->md_module;
 106                         }
 107                 }
 108
 109                 // Register the absence of a dependency row too
 110                 foreach ( array_diff( $modules, $modulesWithDeps ) as $name ) {
 111                         $module = $this->getModule( $name );
 112                         if ( $module ) {
 113                                 $this->getModule( $name )->setFileDependencies( $skin, array() );
 114                         }
 115                 }
 116
 117                 // Get message blob mtimes. Only do this for modules with messages
 118                 $modulesWithMessages = array();
 119                 foreach ( $modules as $name ) {
 120                         $module = $this->getModule( $name );
 121                         if ( $module && count( $module->getMessages() ) ) {
 122                                 $modulesWithMessages[] = $name;
 123                         }
 124                 }
 125                 $modulesWithoutMessages = array_flip( $modules ); // Will be trimmed down by the loop below
 126                 if ( count( $modulesWithMessages ) ) {
 127                         $res = $dbr->select( 'msg_resource', array( 'mr_resource', 'mr_timestamp' ), array(
 128                                         'mr_resource' => $modulesWithMessages,
 129                                         'mr_lang' => $lang
 130                                 ), __METHOD__
 131                         );
 132                         foreach ( $res as $row ) {
 133                                 $module = $this->getModule( $row->mr_resource );
 134                                 if ( $module ) {
 135                                         $module->setMsgBlobMtime( $lang, wfTimestamp( TS_UNIX, $row->mr_timestamp ) );
 136                                         unset( $modulesWithoutMessages[$row->mr_resource] );
 137                                 }
 138                         }
 139                 }
 140                 foreach ( array_keys( $modulesWithoutMessages ) as $name ) {
 141                         $module = $this->getModule( $name );
 142                         if ( $module ) {
 143                                 $module->setMsgBlobMtime( $lang, 0 );
 144                         }
 145                 }
 146         }
 147
 148         /**
 149          * Run JavaScript or CSS data through a filter, caching the filtered result for future calls.
 150          *
 151          * Available filters are:
 152          *
 153          *    - minify-js \see JavaScriptMinifier::minify
 154          *    - minify-css \see CSSMin::minify
 155          *
 156          * If $data is empty, only contains whitespace or the filter was unknown,
 157          * $data is returned unmodified.
 158          *
 159          * @param string $filter Name of filter to run
 160          * @param string $data Text to filter, such as JavaScript or CSS text
 161          * @param string $cacheReport Whether to include the cache key report
 162          * @return string Filtered data, or a comment containing an error message
 163          */
 164         public function filter( $filter, $data, $cacheReport = true ) {
 165                 wfProfileIn( __METHOD__ );
 166
 167                 // For empty/whitespace-only data or for unknown filters, don't perform
 168                 // any caching or processing
 169                 if ( trim( $data ) === '' || !in_array( $filter, array( 'minify-js', 'minify-css' ) ) ) {
 170                         wfProfileOut( __METHOD__ );
 171                         return $data;
 172                 }
 173
 174                 // Try for cache hit
 175                 // Use CACHE_ANYTHING since filtering is very slow compared to DB queries
 176                 $key = wfMemcKey( 'resourceloader', 'filter', $filter, self::$filterCacheVersion, md5( $data ) );
 177                 $cache = wfGetCache( CACHE_ANYTHING );
 178                 $cacheEntry = $cache->get( $key );
 179                 if ( is_string( $cacheEntry ) ) {
 180                         wfIncrStats( "rl-$filter-cache-hits" );
 181                         wfProfileOut( __METHOD__ );
 182                         return $cacheEntry;
 183                 }
 184
 185                 $result = '';
 186                 // Run the filter - we've already verified one of these will work
 187                 try {
 188                         wfIncrStats( "rl-$filter-cache-misses" );
 189                         switch ( $filter ) {
 190                                 case 'minify-js':
 191                                         $result = JavaScriptMinifier::minify( $data,
 192                                                 $this->config->get( 'ResourceLoaderMinifierStatementsOnOwnLine' ),
 193                                                 $this->config->get( 'ResourceLoaderMinifierMaxLineLength' )
 194                                         );
 195                                         if ( $cacheReport ) {
 196                                                 $result .= "\n/* cache key: $key */";
 197                                         }
 198                                         break;
 199                                 case 'minify-css':
 200                                         $result = CSSMin::minify( $data );
 201                                         if ( $cacheReport ) {
 202                                                 $result .= "\n/* cache key: $key */";
 203                                         }
 204                                         break;
 205                         }
 206
 207                         // Save filtered text to Memcached
 208                         $cache->set( $key, $result );
 209                 } catch ( Exception $e ) {
 210                         MWExceptionHandler::logException( $e );
 211                         wfDebugLog( 'resourceloader', __METHOD__ . ": minification failed: $e" );
 212                         $this->hasErrors = true;
 213                         // Return exception as a comment
 214                         $result = self::formatException( $e );
 215                 }
 216
 217                 wfProfileOut( __METHOD__ );
 218
 219                 return $result;
 220         }
 221
 222         /* Methods */
 223
 224         /**
 225          * Register core modules and runs registration hooks.
 226          * @param Config|null $config
 227          */
 228         public function __construct( Config $config = null ) {
 229                 global $IP;
 230
 231                 wfProfileIn( __METHOD__ );
 232
 233                 if ( $config === null ) {
 234                         wfDebug( __METHOD__ . ' was called without providing a Config instance' );
 235                         $config = ConfigFactory::getDefaultInstance()->makeConfig( 'main' );
 236                 }
 237
 238                 $this->config = $config;
 239
 240                 // Add 'local' source first
 241                 $this->addSource( 'local', wfScript( 'load' ) );
 242
 243                 // Add other sources
 244                 $this->addSource( $config->get( 'ResourceLoaderSources' ) );
 245
 246                 // Register core modules
 247                 $this->register( include "$IP/resources/Resources.php" );
 248                 // Register extension modules
 249                 wfRunHooks( 'ResourceLoaderRegisterModules', array( &$this ) );
 250                 $this->register( $config->get( 'ResourceModules' ) );
 251
 252                 if ( $config->get( 'EnableJavaScriptTest' ) === true ) {
 253                         $this->registerTestModules();
 254                 }
 255
 256                 wfProfileOut( __METHOD__ );
 257         }
 258
 259         /**
 260          * @return Config
 261          */
 262         public function getConfig() {
 263                 return $this->config;
 264         }
 265
 266         /**
 267          * Register a module with the ResourceLoader system.
 268          *
 269          * @param mixed $name Name of module as a string or List of name/object pairs as an array
 270          * @param array $info Module info array. For backwards compatibility with 1.17alpha,
 271          *   this may also be a ResourceLoaderModule object. Optional when using
 272          *   multiple-registration calling style.
 273          * @throws MWException If a duplicate module registration is attempted
 274          * @throws MWException If a module name contains illegal characters (pipes or commas)
 275          * @throws MWException If something other than a ResourceLoaderModule is being registered
 276          * @return bool False if there were any errors, in which case one or more modules were
 277          *   not registered
 278          */
 279         public function register( $name, $info = null ) {
 280                 wfProfileIn( __METHOD__ );
 281
 282                 // Allow multiple modules to be registered in one call
 283                 $registrations = is_array( $name ) ? $name : array( $name => $info );
 284                 foreach ( $registrations as $name => $info ) {
 285                         // Disallow duplicate registrations
 286                         if ( isset( $this->moduleInfos[$name] ) ) {
 287                                 wfProfileOut( __METHOD__ );
 288                                 // A module has already been registered by this name
 289                                 throw new MWException(
 290                                         'ResourceLoader duplicate registration error. ' .
 291                                         'Another module has already been registered as ' . $name
 292                                 );
 293                         }
 294
 295                         // Check $name for validity
 296                         if ( !self::isValidModuleName( $name ) ) {
 297                                 wfProfileOut( __METHOD__ );
 298                                 throw new MWException( "ResourceLoader module name '$name' is invalid, "
 299                                         . "see ResourceLoader::isValidModuleName()" );
 300                         }
 301
 302                         // Attach module
 303                         if ( $info instanceof ResourceLoaderModule ) {
 304                                 $this->moduleInfos[$name] = array( 'object' => $info );
 305                                 $info->setName( $name );
 306                                 $this->modules[$name] = $info;
 307                         } elseif ( is_array( $info ) ) {
 308                                 // New calling convention
 309                                 $this->moduleInfos[$name] = $info;
 310                         } else {
 311                                 wfProfileOut( __METHOD__ );
 312                                 throw new MWException(
 313                                         'ResourceLoader module info type error for module \'' . $name .
 314                                         '\': expected ResourceLoaderModule or array (got: ' . gettype( $info ) . ')'
 315                                 );
 316                         }
 317
 318                         // Last-minute changes
 319
 320                         // Apply custom skin-defined styles to existing modules.
 321                         if ( $this->isFileModule( $name ) ) {
 322                                 foreach ( $this->config->get( 'ResourceModuleSkinStyles' ) as $skinName => $skinStyles ) {
 323                                         // If this module already defines skinStyles for this skin, ignore $wgResourceModuleSkinStyles.
 324                                         if ( isset( $this->moduleInfos[$name]['skinStyles'][$skinName] ) ) {
 325                                                 continue;
 326                                         }
 327
 328                                         // If $name is preceded with a '+', the defined style files will be added to 'default'
 329                                         // skinStyles, otherwise 'default' will be ignored as it normally would be.
 330                                         if ( isset( $skinStyles[$name] ) ) {
 331                                                 $paths = (array)$skinStyles[$name];
 332                                                 $styleFiles = array();
 333                                         } elseif ( isset( $skinStyles['+' . $name] ) ) {
 334                                                 $paths = (array)$skinStyles['+' . $name];
 335                                                 $styleFiles = isset( $this->moduleInfos[$name]['skinStyles']['default'] ) ?
 336                                                         $this->moduleInfos[$name]['skinStyles']['default'] :
 337                                                         array();
 338                                         } else {
 339                                                 continue;
 340                                         }
 341
 342                                         // Add new file paths, remapping them to refer to our directories and not use settings
 343                                         // from the module we're modifying. These can come from the base definition or be defined
 344                                         // for each module.
 345                                         list( $localBasePath, $remoteBasePath ) =
 346                                                 ResourceLoaderFileModule::extractBasePaths( $skinStyles );
 347                                         list( $localBasePath, $remoteBasePath ) =
 348                                                 ResourceLoaderFileModule::extractBasePaths( $paths, $localBasePath, $remoteBasePath );
 349
 350                                         foreach ( $paths as $path ) {
 351                                                 $styleFiles[] = new ResourceLoaderFilePath( $path, $localBasePath, $remoteBasePath );
 352                                         }
 353
 354                                         $this->moduleInfos[$name]['skinStyles'][$skinName] = $styleFiles;
 355                                 }
 356                         }
 357                 }
 358
 359                 wfProfileOut( __METHOD__ );
 360         }
 361
 362         /**
 363          */
 364         public function registerTestModules() {
 365                 global $IP;
 366
 367                 if ( $this->config->get( 'EnableJavaScriptTest' ) !== true ) {
 368                         throw new MWException( 'Attempt to register JavaScript test modules '
 369                                 . 'but <code>$wgEnableJavaScriptTest</code> is false. '
 370                                 . 'Edit your <code>LocalSettings.php</code> to enable it.' );
 371                 }
 372
 373                 wfProfileIn( __METHOD__ );
 374
 375                 // Get core test suites
 376                 $testModules = array();
 377                 $testModules['qunit'] = array();
 378                 // Get other test suites (e.g. from extensions)
 379                 wfRunHooks( 'ResourceLoaderTestModules', array( &$testModules, &$this ) );
 380
 381                 // Add the testrunner (which configures QUnit) to the dependencies.
 382                 // Since it must be ready before any of the test suites are executed.
 383                 foreach ( $testModules['qunit'] as &$module ) {
 384                         // Make sure all test modules are top-loading so that when QUnit starts
 385                         // on document-ready, it will run once and finish. If some tests arrive
 386                         // later (possibly after QUnit has already finished) they will be ignored.
 387                         $module['position'] = 'top';
 388                         $module['dependencies'][] = 'test.mediawiki.qunit.testrunner';
 389                 }
 390
 391                 $testModules['qunit'] =
 392                         ( include "$IP/tests/qunit/QUnitTestResources.php" ) + $testModules['qunit'];
 393
 394                 foreach ( $testModules as $id => $names ) {
 395                         // Register test modules
 396                         $this->register( $testModules[$id] );
 397
 398                         // Keep track of their names so that they can be loaded together
 399                         $this->testModuleNames[$id] = array_keys( $testModules[$id] );
 400                 }
 401
 402                 wfProfileOut( __METHOD__ );
 403         }
 404
 405         /**
 406          * Add a foreign source of modules.
 407          *
 408          * @param array|string $id Source ID (string), or array( id1 => loadUrl, id2 => loadUrl, ... )
 409          * @param string|array $loadUrl load.php url (string), or array with loadUrl key for
 410          *  backwards-compatibility.
 411          * @throws MWException
 412          */
 413         public function addSource( $id, $loadUrl = null ) {
 414                 // Allow multiple sources to be registered in one call
 415                 if ( is_array( $id ) ) {
 416                         foreach ( $id as $key => $value ) {
 417                                 $this->addSource( $key, $value );
 418                         }
 419                         return;
 420                 }
 421
 422                 // Disallow duplicates
 423                 if ( isset( $this->sources[$id] ) ) {
 424                         throw new MWException(
 425                                 'ResourceLoader duplicate source addition error. ' .
 426                                 'Another source has already been registered as ' . $id
 427                         );
 428                 }
 429
 430                 // Pre 1.24 backwards-compatibility
 431                 if ( is_array( $loadUrl ) ) {
 432                         if ( !isset( $loadUrl['loadScript'] ) ) {
 433                                 throw new MWException(
 434                                         __METHOD__ . ' was passed an array with no "loadScript" key.'
 435                                 );
 436                         }
 437
 438                         $loadUrl = $loadUrl['loadScript'];
 439                 }
 440
 441                 $this->sources[$id] = $loadUrl;
 442         }
 443
 444         /**
 445          * Get a list of module names.
 446          *
 447          * @return array List of module names
 448          */
 449         public function getModuleNames() {
 450                 return array_keys( $this->moduleInfos );
 451         }
 452
 453         /**
 454          * Get a list of test module names for one (or all) frameworks.
 455          *
 456          * If the given framework id is unknkown, or if the in-object variable is not an array,
 457          * then it will return an empty array.
 458          *
 459          * @param string $framework Get only the test module names for one
 460          *   particular framework (optional)
 461          * @return array
 462          */
 463         public function getTestModuleNames( $framework = 'all' ) {
 464                 /** @todo api siteinfo prop testmodulenames modulenames */
 465                 if ( $framework == 'all' ) {
 466                         return $this->testModuleNames;
 467                 } elseif ( isset( $this->testModuleNames[$framework] )
 468                         && is_array( $this->testModuleNames[$framework] )
 469                 ) {
 470                         return $this->testModuleNames[$framework];
 471                 } else {
 472                         return array();
 473                 }
 474         }
 475
 476         /**
 477          * Get the ResourceLoaderModule object for a given module name.
 478          *
 479          * If an array of module parameters exists but a ResourceLoaderModule object has not
 480          * yet been instantiated, this method will instantiate and cache that object such that
 481          * subsequent calls simply return the same object.
 482          *
 483          * @param string $name Module name
 484          * @return ResourceLoaderModule|null If module has been registered, return a
 485          *  ResourceLoaderModule instance. Otherwise, return null.
 486          */
 487         public function getModule( $name ) {
 488                 if ( !isset( $this->modules[$name] ) ) {
 489                         if ( !isset( $this->moduleInfos[$name] ) ) {
 490                                 // No such module
 491                                 return null;
 492                         }
 493                         // Construct the requested object
 494                         $info = $this->moduleInfos[$name];
 495                         /** @var ResourceLoaderModule $object */
 496                         if ( isset( $info['object'] ) ) {
 497                                 // Object given in info array
 498                                 $object = $info['object'];
 499                         } else {
 500                                 if ( !isset( $info['class'] ) ) {
 501                                         $class = 'ResourceLoaderFileModule';
 502                                 } else {
 503                                         $class = $info['class'];
 504                                 }
 505                                 /** @var ResourceLoaderModule $object */
 506                                 $object = new $class( $info );
 507                                 $object->setConfig( $this->getConfig() );
 508                         }
 509                         $object->setName( $name );
 510                         $this->modules[$name] = $object;
 511                 }
 512
 513                 return $this->modules[$name];
 514         }
 515
 516         /**
 517          * Return whether the definition of a module corresponds to a simple ResourceLoaderFileModule.
 518          *
 519          * @param string $name Module name
 520          * @return bool
 521          */
 522         protected function isFileModule( $name ) {
 523                 if ( !isset( $this->moduleInfos[$name] ) ) {
 524                         return false;
 525                 }
 526                 $info = $this->moduleInfos[$name];
 527                 if ( isset( $info['object'] ) || isset( $info['class'] ) ) {
 528                         return false;
 529                 }
 530                 return true;
 531         }
 532
 533         /**
 534          * Get the list of sources.
 535          *
 536          * @return array Like array( id => load.php url, .. )
 537          */
 538         public function getSources() {
 539                 return $this->sources;
 540         }
 541
 542         /**
 543          * Get the URL to the load.php endpoint for the given
 544          * ResourceLoader source
 545          *
 546          * @since 1.24
 547          * @param string $source
 548          * @throws MWException On an invalid $source name
 549          * @return string
 550          */
 551         public function getLoadScript( $source ) {
 552                 if ( !isset( $this->sources[$source] ) ) {
 553                         throw new MWException( "The $source source was never registered in ResourceLoader." );
 554                 }
 555                 return $this->sources[$source];
 556         }
 557
 558         /**
 559          * Output a response to a load request, including the content-type header.
 560          *
 561          * @param ResourceLoaderContext $context Context in which a response should be formed
 562          */
 563         public function respond( ResourceLoaderContext $context ) {
 564                 // Use file cache if enabled and available...
 565                 if ( $this->config->get( 'UseFileCache' ) ) {
 566                         $fileCache = ResourceFileCache::newFromContext( $context );
 567                         if ( $this->tryRespondFromFileCache( $fileCache, $context ) ) {
 568                                 return; // output handled
 569                         }
 570                 }
 571
 572                 // Buffer output to catch warnings. Normally we'd use ob_clean() on the
 573                 // top-level output buffer to clear warnings, but that breaks when ob_gzhandler
 574                 // is used: ob_clean() will clear the GZIP header in that case and it won't come
 575                 // back for subsequent output, resulting in invalid GZIP. So we have to wrap
 576                 // the whole thing in our own output buffer to be sure the active buffer
 577                 // doesn't use ob_gzhandler.
 578                 // See http://bugs.php.net/bug.php?id=36514
 579                 ob_start();
 580
 581                 wfProfileIn( __METHOD__ );
 582                 $errors = '';
 583
 584                 // Find out which modules are missing and instantiate the others
 585                 $modules = array();
 586                 $missing = array();
 587                 foreach ( $context->getModules() as $name ) {
 588                         $module = $this->getModule( $name );
 589                         if ( $module ) {
 590                                 // Do not allow private modules to be loaded from the web.
 591                                 // This is a security issue, see bug 34907.
 592                                 if ( $module->getGroup() === 'private' ) {
 593                                         wfDebugLog( 'resourceloader', __METHOD__ . ": request for private module '$name' denied" );
 594                                         $this->hasErrors = true;
 595                                         // Add exception to the output as a comment
 596                                         $errors .= self::makeComment( "Cannot show private module \"$name\"" );
 597
 598                                         continue;
 599                                 }
 600                                 $modules[$name] = $module;
 601                         } else {
 602                                 $missing[] = $name;
 603                         }
 604                 }
 605
 606                 // Preload information needed to the mtime calculation below
 607                 try {
 608                         $this->preloadModuleInfo( array_keys( $modules ), $context );
 609                 } catch ( Exception $e ) {
 610                         MWExceptionHandler::logException( $e );
 611                         wfDebugLog( 'resourceloader', __METHOD__ . ": preloading module info failed: $e" );
 612                         $this->hasErrors = true;
 613                         // Add exception to the output as a comment
 614                         $errors .= self::formatException( $e );
 615                 }
 616
 617                 wfProfileIn( __METHOD__ . '-getModifiedTime' );
 618
 619                 // To send Last-Modified and support If-Modified-Since, we need to detect
 620                 // the last modified time
 621                 $mtime = wfTimestamp( TS_UNIX, $this->config->get( 'CacheEpoch' ) );
 622                 foreach ( $modules as $module ) {
 623                         /**
 624                          * @var $module ResourceLoaderModule
 625                          */
 626                         try {
 627                                 // Calculate maximum modified time
 628                                 $mtime = max( $mtime, $module->getModifiedTime( $context ) );
 629                         } catch ( Exception $e ) {
 630                                 MWExceptionHandler::logException( $e );
 631                                 wfDebugLog( 'resourceloader', __METHOD__ . ": calculating maximum modified time failed: $e" );
 632                                 $this->hasErrors = true;
 633                                 // Add exception to the output as a comment
 634                                 $errors .= self::formatException( $e );
 635                         }
 636                 }
 637
 638                 wfProfileOut( __METHOD__ . '-getModifiedTime' );
 639
 640                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 641                 if ( $this->tryRespondLastModified( $context, $mtime ) ) {
 642                         wfProfileOut( __METHOD__ );
 643                         return; // output handled (buffers cleared)
 644                 }
 645
 646                 // Generate a response
 647                 $response = $this->makeModuleResponse( $context, $modules, $missing );
 648
 649                 // Prepend comments indicating exceptions
 650                 $response = $errors . $response;
 651
 652                 // Capture any PHP warnings from the output buffer and append them to the
 653                 // response in a comment if we're in debug mode.
 654                 if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 655                         $response = self::makeComment( $warnings ) . $response;
 656                         $this->hasErrors = true;
 657                 }
 658
 659                 // Save response to file cache unless there are errors
 660                 if ( isset( $fileCache ) && !$errors && !count( $missing ) ) {
 661                         // Cache single modules...and other requests if there are enough hits
 662                         if ( ResourceFileCache::useFileCache( $context ) ) {
 663                                 if ( $fileCache->isCacheWorthy() ) {
 664                                         $fileCache->saveText( $response );
 665                                 } else {
 666                                         $fileCache->incrMissesRecent( $context->getRequest() );
 667                                 }
 668                         }
 669                 }
 670
 671                 // Send content type and cache related headers
 672                 $this->sendResponseHeaders( $context, $mtime, $this->hasErrors );
 673
 674                 // Remove the output buffer and output the response
 675                 ob_end_clean();
 676                 echo $response;
 677
 678                 wfProfileOut( __METHOD__ );
 679         }
 680
 681         /**
 682          * Send content type and last modified headers to the client.
 683          * @param ResourceLoaderContext $context
 684          * @param string $mtime TS_MW timestamp to use for last-modified
 685          * @param bool $errors Whether there are commented-out errors in the response
 686          * @return void
 687          */
 688         protected function sendResponseHeaders( ResourceLoaderContext $context, $mtime, $errors ) {
 689                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 690                 // If a version wasn't specified we need a shorter expiry time for updates
 691                 // to propagate to clients quickly
 692                 // If there were errors, we also need a shorter expiry time so we can recover quickly
 693                 if ( is_null( $context->getVersion() ) || $errors ) {
 694                         $maxage = $rlMaxage['unversioned']['client'];
 695                         $smaxage = $rlMaxage['unversioned']['server'];
 696                 // If a version was specified we can use a longer expiry time since changing
 697                 // version numbers causes cache misses
 698                 } else {
 699                         $maxage = $rlMaxage['versioned']['client'];
 700                         $smaxage = $rlMaxage['versioned']['server'];
 701                 }
 702                 if ( $context->getOnly() === 'styles' ) {
 703                         header( 'Content-Type: text/css; charset=utf-8' );
 704                         header( 'Access-Control-Allow-Origin: *' );
 705                 } else {
 706                         header( 'Content-Type: text/javascript; charset=utf-8' );
 707                 }
 708                 header( 'Last-Modified: ' . wfTimestamp( TS_RFC2822, $mtime ) );
 709                 if ( $context->getDebug() ) {
 710                         // Do not cache debug responses
 711                         header( 'Cache-Control: private, no-cache, must-revalidate' );
 712                         header( 'Pragma: no-cache' );
 713                 } else {
 714                         header( "Cache-Control: public, max-age=$maxage, s-maxage=$smaxage" );
 715                         $exp = min( $maxage, $smaxage );
 716                         header( 'Expires: ' . wfTimestamp( TS_RFC2822, $exp + time() ) );
 717                 }
 718         }
 719
 720         /**
 721          * Respond with 304 Last Modified if appropiate.
 722          *
 723          * If there's an If-Modified-Since header, respond with a 304 appropriately
 724          * and clear out the output buffer. If the client cache is too old then do nothing.
 725          *
 726          * @param ResourceLoaderContext $context
 727          * @param string $mtime The TS_MW timestamp to check the header against
 728          * @return bool True if 304 header sent and output handled
 729          */
 730         protected function tryRespondLastModified( ResourceLoaderContext $context, $mtime ) {
 731                 // If there's an If-Modified-Since header, respond with a 304 appropriately
 732                 // Some clients send "timestamp;length=123". Strip the part after the first ';'
 733                 // so we get a valid timestamp.
 734                 $ims = $context->getRequest()->getHeader( 'If-Modified-Since' );
 735                 // Never send 304s in debug mode
 736                 if ( $ims !== false && !$context->getDebug() ) {
 737                         $imsTS = strtok( $ims, ';' );
 738                         if ( $mtime <= wfTimestamp( TS_UNIX, $imsTS ) ) {
 739                                 // There's another bug in ob_gzhandler (see also the comment at
 740                                 // the top of this function) that causes it to gzip even empty
 741                                 // responses, meaning it's impossible to produce a truly empty
 742                                 // response (because the gzip header is always there). This is
 743                                 // a problem because 304 responses have to be completely empty
 744                                 // per the HTTP spec, and Firefox behaves buggily when they're not.
 745                                 // See also http://bugs.php.net/bug.php?id=51579
 746                                 // To work around this, we tear down all output buffering before
 747                                 // sending the 304.
 748                                 wfResetOutputBuffers( /* $resetGzipEncoding = */ true );
 749
 750                                 header( 'HTTP/1.0 304 Not Modified' );
 751                                 header( 'Status: 304 Not Modified' );
 752                                 return true;
 753                         }
 754                 }
 755                 return false;
 756         }
 757
 758         /**
 759          * Send out code for a response from file cache if possible.
 760          *
 761          * @param ResourceFileCache $fileCache Cache object for this request URL
 762          * @param ResourceLoaderContext $context Context in which to generate a response
 763          * @return bool If this found a cache file and handled the response
 764          */
 765         protected function tryRespondFromFileCache(
 766                 ResourceFileCache $fileCache, ResourceLoaderContext $context
 767         ) {
 768                 $rlMaxage = $this->config->get( 'ResourceLoaderMaxage' );
 769                 // Buffer output to catch warnings.
 770                 ob_start();
 771                 // Get the maximum age the cache can be
 772                 $maxage = is_null( $context->getVersion() )
 773                         ? $rlMaxage['unversioned']['server']
 774                         : $rlMaxage['versioned']['server'];
 775                 // Minimum timestamp the cache file must have
 776                 $good = $fileCache->isCacheGood( wfTimestamp( TS_MW, time() - $maxage ) );
 777                 if ( !$good ) {
 778                         try { // RL always hits the DB on file cache miss...
 779                                 wfGetDB( DB_SLAVE );
 780                         } catch ( DBConnectionError $e ) { // ...check if we need to fallback to cache
 781                                 $good = $fileCache->isCacheGood(); // cache existence check
 782                         }
 783                 }
 784                 if ( $good ) {
 785                         $ts = $fileCache->cacheTimestamp();
 786                         // Send content type and cache headers
 787                         $this->sendResponseHeaders( $context, $ts, false );
 788                         // If there's an If-Modified-Since header, respond with a 304 appropriately
 789                         if ( $this->tryRespondLastModified( $context, $ts ) ) {
 790                                 return false; // output handled (buffers cleared)
 791                         }
 792                         $response = $fileCache->fetchText();
 793                         // Capture any PHP warnings from the output buffer and append them to the
 794                         // response in a comment if we're in debug mode.
 795                         if ( $context->getDebug() && strlen( $warnings = ob_get_contents() ) ) {
 796                                 $response = "/*\n$warnings\n*/\n" . $response;
 797                         }
 798                         // Remove the output buffer and output the response
 799                         ob_end_clean();
 800                         echo $response . "\n/* Cached {$ts} */";
 801                         return true; // cache hit
 802                 }
 803                 // Clear buffer
 804                 ob_end_clean();
 805
 806                 return false; // cache miss
 807         }
 808
 809         /**
 810          * Generate a CSS or JS comment block.
 811          *
 812          * Only use this for public data, not error message details.
 813          *
 814          * @param string $text
 815          * @return string
 816          */
 817         public static function makeComment( $text ) {
 818                 $encText = str_replace( '*/', '* /', $text );
 819                 return "/*\n$encText\n*/\n";
 820         }
 821
 822         /**
 823          * Handle exception display.
 824          *
 825          * @param Exception $e Exception to be shown to the user
 826          * @return string Sanitized text that can be returned to the user
 827          */
 828         public static function formatException( $e ) {
 829                 global $wgShowExceptionDetails;
 830
 831                 if ( $wgShowExceptionDetails ) {
 832                         return self::makeComment( $e->__toString() );
 833                 } else {
 834                         return self::makeComment( wfMessage( 'internalerror' )->text() );
 835                 }
 836         }
 837
 838         /**
 839          * Generate code for a response.
 840          *
 841          * @param ResourceLoaderContext $context Context in which to generate a response
 842          * @param array $modules List of module objects keyed by module name
 843          * @param array $missing List of requested module names that are unregistered (optional)
 844          * @return string Response data
 845          */
 846         public function makeModuleResponse( ResourceLoaderContext $context,
 847                 array $modules, array $missing = array()
 848         ) {
 849                 $out = '';
 850                 $exceptions = '';
 851                 $states = array();
 852
 853                 if ( !count( $modules ) && !count( $missing ) ) {
 854                         return "/* This file is the Web entry point for MediaWiki's ResourceLoader:
 855    <https://www.mediawiki.org/wiki/ResourceLoader>. In this request,
 856    no modules were requested. Max made me put this here. */";
 857                 }
 858
 859                 wfProfileIn( __METHOD__ );
 860
 861                 // Pre-fetch blobs
 862                 if ( $context->shouldIncludeMessages() ) {
 863                         try {
 864                                 $blobs = MessageBlobStore::getInstance()->get( $this, $modules, $context->getLanguage() );
 865                         } catch ( Exception $e ) {
 866                                 MWExceptionHandler::logException( $e );
 867                                 wfDebugLog(
 868                                         'resourceloader',
 869                                         __METHOD__ . ": pre-fetching blobs from MessageBlobStore failed: $e"
 870                                 );
 871                                 $this->hasErrors = true;
 872                                 // Add exception to the output as a comment
 873                                 $exceptions .= self::formatException( $e );
 874                         }
 875                 } else {
 876                         $blobs = array();
 877                 }
 878
 879                 foreach ( $missing as $name ) {
 880                         $states[$name] = 'missing';
 881                 }
 882
 883                 // Generate output
 884                 $isRaw = false;
 885                 foreach ( $modules as $name => $module ) {
 886                         /**
 887                          * @var $module ResourceLoaderModule
 888                          */
 889
 890                         wfProfileIn( __METHOD__ . '-' . $name );
 891                         try {
 892                                 $scripts = '';
 893                                 if ( $context->shouldIncludeScripts() ) {
 894                                         // If we are in debug mode, we'll want to return an array of URLs if possible
 895                                         // However, we can't do this if the module doesn't support it
 896                                         // We also can't do this if there is an only= parameter, because we have to give
 897                                         // the module a way to return a load.php URL without causing an infinite loop
 898                                         if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 899                                                 $scripts = $module->getScriptURLsForDebug( $context );
 900                                         } else {
 901                                                 $scripts = $module->getScript( $context );
 902                                                 // rtrim() because there are usually a few line breaks
 903                                                 // after the last ';'. A new line at EOF, a new line
 904                                                 // added by ResourceLoaderFileModule::readScriptFiles, etc.
 905                                                 if ( is_string( $scripts )
 906                                                         && strlen( $scripts )
 907                                                         && substr( rtrim( $scripts ), -1 ) !== ';'
 908                                                 ) {
 909                                                         // Append semicolon to prevent weird bugs caused by files not
 910                                                         // terminating their statements right (bug 27054)
 911                                                         $scripts .= ";\n";
 912                                                 }
 913                                         }
 914                                 }
 915                                 // Styles
 916                                 $styles = array();
 917                                 if ( $context->shouldIncludeStyles() ) {
 918                                         // Don't create empty stylesheets like array( '' => '' ) for modules
 919                                         // that don't *have* any stylesheets (bug 38024).
 920                                         $stylePairs = $module->getStyles( $context );
 921                                         if ( count( $stylePairs ) ) {
 922                                                 // If we are in debug mode without &only= set, we'll want to return an array of URLs
 923                                                 // See comment near shouldIncludeScripts() for more details
 924                                                 if ( $context->getDebug() && !$context->getOnly() && $module->supportsURLLoading() ) {
 925                                                         $styles = array(
 926                                                                 'url' => $module->getStyleURLsForDebug( $context )
 927                                                         );
 928                                                 } else {
 929                                                         // Minify CSS before embedding in mw.loader.implement call
 930                                                         // (unless in debug mode)
 931                                                         if ( !$context->getDebug() ) {
 932                                                                 foreach ( $stylePairs as $media => $style ) {
 933                                                                         // Can be either a string or an array of strings.
 934                                                                         if ( is_array( $style ) ) {
 935                                                                                 $stylePairs[$media] = array();
 936                                                                                 foreach ( $style as $cssText ) {
 937                                                                                         if ( is_string( $cssText ) ) {
 938                                                                                                 $stylePairs[$media][] = $this->filter( 'minify-css', $cssText );
 939                                                                                         }
 940                                                                                 }
 941                                                                         } elseif ( is_string( $style ) ) {
 942                                                                                 $stylePairs[$media] = $this->filter( 'minify-css', $style );
 943                                                                         }
 944                                                                 }
 945                                                         }
 946                                                         // Wrap styles into @media groups as needed and flatten into a numerical array
 947                                                         $styles = array(
 948                                                                 'css' => self::makeCombinedStyles( $stylePairs )
 949                                                         );
 950                                                 }
 951                                         }
 952                                 }
 953
 954                                 // Messages
 955                                 $messagesBlob = isset( $blobs[$name] ) ? $blobs[$name] : '{}';
 956
 957                                 // Append output
 958                                 switch ( $context->getOnly() ) {
 959                                         case 'scripts':
 960                                                 if ( is_string( $scripts ) ) {
 961                                                         // Load scripts raw...
 962                                                         $out .= $scripts;
 963                                                 } elseif ( is_array( $scripts ) ) {
 964                                                         // ...except when $scripts is an array of URLs
 965                                                         $out .= self::makeLoaderImplementScript( $name, $scripts, array(), array() );
 966                                                 }
 967                                                 break;
 968                                         case 'styles':
 969                                                 // We no longer seperate into media, they are all combined now with
 970                                                 // custom media type groups into @media .. {} sections as part of the css string.
 971                                                 // Module returns either an empty array or a numerical array with css strings.
 972                                                 $out .= isset( $styles['css'] ) ? implode( '', $styles['css'] ) : '';
 973                                                 break;
 974                                         case 'messages':
 975                                                 $out .= self::makeMessageSetScript( new XmlJsCode( $messagesBlob ) );
 976                                                 break;
 977                                         case 'templates':
 978                                                 $out .= Xml::encodeJsCall(
 979                                                         'mw.templates.set',
 980                                                         array( $name, (object)$module->getTemplates() ),
 981                                                         ResourceLoader::inDebugMode()
 982                                                 );
 983                                                 break;
 984                                         default:
 985                                                 $out .= self::makeLoaderImplementScript(
 986                                                         $name,
 987                                                         $scripts,
 988                                                         $styles,
 989                                                         new XmlJsCode( $messagesBlob ),
 990                                                         $module->getTemplates()
 991                                                 );
 992                                                 break;
 993                                 }
 994                         } catch ( Exception $e ) {
 995                                 MWExceptionHandler::logException( $e );
 996                                 wfDebugLog( 'resourceloader', __METHOD__ . ": generating module package failed: $e" );
 997                                 $this->hasErrors = true;
 998                                 // Add exception to the output as a comment
 999                                 $exceptions .= self::formatException( $e );
1000
1001                                 // Respond to client with error-state instead of module implementation
1002                                 $states[$name] = 'error';
1003                                 unset( $modules[$name] );
1004                         }
1005                         $isRaw |= $module->isRaw();
1006                         wfProfileOut( __METHOD__ . '-' . $name );
1007                 }
1008
1009                 // Update module states
1010                 if ( $context->shouldIncludeScripts() && !$context->getRaw() && !$isRaw ) {
1011                         if ( count( $modules ) && $context->getOnly() === 'scripts' ) {
1012                                 // Set the state of modules loaded as only scripts to ready as
1013                                 // they don't have an mw.loader.implement wrapper that sets the state
1014                                 foreach ( $modules as $name => $module ) {
1015                                         $states[$name] = 'ready';
1016                                 }
1017                         }
1018
1019                         // Set the state of modules we didn't respond to with mw.loader.implement
1020                         if ( count( $states ) ) {
1021                                 $out .= self::makeLoaderStateScript( $states );
1022                         }
1023                 } else {
1024                         if ( count( $states ) ) {
1025                                 $exceptions .= self::makeComment(
1026                                         'Problematic modules: ' . FormatJson::encode( $states, ResourceLoader::inDebugMode() )
1027                                 );
1028                         }
1029                 }
1030
1031                 if ( !$context->getDebug() ) {
1032                         if ( $context->getOnly() === 'styles' ) {
1033                                 $out = $this->filter( 'minify-css', $out );
1034                         } else {
1035                                 $out = $this->filter( 'minify-js', $out );
1036                         }
1037                 }
1038
1039                 wfProfileOut( __METHOD__ );
1040                 return $exceptions . $out;
1041         }
1042
1043         /* Static Methods */
1044
1045         /**
1046          * Return JS code that calls mw.loader.implement with given module properties.
1047          *
1048          * @param string $name Module name
1049          * @param mixed $scripts List of URLs to JavaScript files or String of JavaScript code
1050          * @param mixed $styles Array of CSS strings keyed by media type, or an array of lists of URLs
1051          *   to CSS files keyed by media type
1052          * @param mixed $messages List of messages associated with this module. May either be an
1053          *   associative array mapping message key to value, or a JSON-encoded message blob containing
1054          *   the same data, wrapped in an XmlJsCode object.
1055          * @param array $templates Keys are name of templates and values are the source of
1056          *   the template.
1057          * @throws MWException
1058          * @return string
1059          */
1060         public static function makeLoaderImplementScript( $name, $scripts, $styles,
1061                 $messages, $templates
1062         ) {
1063                 if ( is_string( $scripts ) ) {
1064                         $scripts = new XmlJsCode( "function ( $, jQuery ) {\n{$scripts}\n}" );
1065                 } elseif ( !is_array( $scripts ) ) {
1066                         throw new MWException( 'Invalid scripts error. Array of URLs or string of code expected.' );
1067                 }
1068
1069                 return Xml::encodeJsCall(
1070                         'mw.loader.implement',
1071                         array(
1072                                 $name,
1073                                 $scripts,
1074                                 // Force objects. mw.loader.implement requires them to be javascript objects.
1075                                 // Although these variables are associative arrays, which become javascript
1076                                 // objects through json_encode. In many cases they will be empty arrays, and
1077                                 // PHP/json_encode() consider empty arrays to be numerical arrays and
1078                                 // output javascript "[]" instead of "{}". This fixes that.
1079                                 (object)$styles,
1080                                 (object)$messages,
1081                                 (object)$templates,
1082                         ),
1083                         ResourceLoader::inDebugMode()
1084                 );
1085         }
1086
1087         /**
1088          * Returns JS code which, when called, will register a given list of messages.
1089          *
1090          * @param mixed $messages Either an associative array mapping message key to value, or a
1091          *   JSON-encoded message blob containing the same data, wrapped in an XmlJsCode object.
1092          * @return string
1093          */
1094         public static function makeMessageSetScript( $messages ) {
1095                 return Xml::encodeJsCall(
1096                         'mw.messages.set',
1097                         array( (object)$messages ),
1098                         ResourceLoader::inDebugMode()
1099                 );
1100         }
1101
1102         /**
1103          * Combines an associative array mapping media type to CSS into a
1104          * single stylesheet with "@media" blocks.
1105          *
1106          * @param array $stylePairs Array keyed by media type containing (arrays of) CSS strings
1107          * @return array
1108          */
1109         public static function makeCombinedStyles( array $stylePairs ) {
1110                 $out = array();
1111                 foreach ( $stylePairs as $media => $styles ) {
1112                         // ResourceLoaderFileModule::getStyle can return the styles
1113                         // as a string or an array of strings. This is to allow separation in
1114                         // the front-end.
1115                         $styles = (array)$styles;
1116                         foreach ( $styles as $style ) {
1117                                 $style = trim( $style );
1118                                 // Don't output an empty "@media print { }" block (bug 40498)
1119                                 if ( $style !== '' ) {
1120                                         // Transform the media type based on request params and config
1121                                         // The way that this relies on $wgRequest to propagate request params is slightly evil
1122                                         $media = OutputPage::transformCssMedia( $media );
1123
1124                                         if ( $media === '' || $media == 'all' ) {
1125                                                 $out[] = $style;
1126                                         } elseif ( is_string( $media ) ) {
1127                                                 $out[] = "@media $media {\n" . str_replace( "\n", "\n\t", "\t" . $style ) . "}";
1128                                         }
1129                                         // else: skip
1130                                 }
1131                         }
1132                 }
1133                 return $out;
1134         }
1135
1136         /**
1137          * Returns a JS call to mw.loader.state, which sets the state of a
1138          * module or modules to a given value. Has two calling conventions:
1139          *
1140          *    - ResourceLoader::makeLoaderStateScript( $name, $state ):
1141          *         Set the state of a single module called $name to $state
1142          *
1143          *    - ResourceLoader::makeLoaderStateScript( array( $name => $state, ... ) ):
1144          *         Set the state of modules with the given names to the given states
1145          *
1146          * @param string $name
1147          * @param string $state
1148          * @return string
1149          */
1150         public static function makeLoaderStateScript( $name, $state = null ) {
1151                 if ( is_array( $name ) ) {
1152                         return Xml::encodeJsCall(
1153                                 'mw.loader.state',
1154                                 array( $name ),
1155                                 ResourceLoader::inDebugMode()
1156                         );
1157                 } else {
1158                         return Xml::encodeJsCall(
1159                                 'mw.loader.state',
1160                                 array( $name, $state ),
1161                                 ResourceLoader::inDebugMode()
1162                         );
1163                 }
1164         }
1165
1166         /**
1167          * Returns JS code which calls the script given by $script. The script will
1168          * be called with local variables name, version, dependencies and group,
1169          * which will have values corresponding to $name, $version, $dependencies
1170          * and $group as supplied.
1171          *
1172          * @param string $name Module name
1173          * @param int $version Module version number as a timestamp
1174          * @param array $dependencies List of module names on which this module depends
1175          * @param string $group Group which the module is in.
1176          * @param string $source Source of the module, or 'local' if not foreign.
1177          * @param string $script JavaScript code
1178          * @return string
1179          */
1180         public static function makeCustomLoaderScript( $name, $version, $dependencies,
1181                 $group, $source, $script
1182         ) {
1183                 $script = str_replace( "\n", "\n\t", trim( $script ) );
1184                 return Xml::encodeJsCall(
1185                         "( function ( name, version, dependencies, group, source ) {\n\t$script\n} )",
1186                         array( $name, $version, $dependencies, $group, $source ),
1187                         ResourceLoader::inDebugMode()
1188                 );
1189         }
1190
1191         /**
1192          * Returns JS code which calls mw.loader.register with the given
1193          * parameters. Has three calling conventions:
1194          *
1195          *   - ResourceLoader::makeLoaderRegisterScript( $name, $version,
1196          *        $dependencies, $group, $source, $skip
1197          *     ):
1198          *        Register a single module.
1199          *
1200          *   - ResourceLoader::makeLoaderRegisterScript( array( $name1, $name2 ) ):
1201          *        Register modules with the given names.
1202          *
1203          *   - ResourceLoader::makeLoaderRegisterScript( array(
1204          *        array( $name1, $version1, $dependencies1, $group1, $source1, $skip1 ),
1205          *        array( $name2, $version2, $dependencies1, $group2, $source2, $skip2 ),
1206          *        ...
1207          *     ) ):
1208          *        Registers modules with the given names and parameters.
1209          *
1210          * @param string $name Module name
1211          * @param int $version Module version number as a timestamp
1212          * @param array $dependencies List of module names on which this module depends
1213          * @param string $group Group which the module is in
1214          * @param string $source Source of the module, or 'local' if not foreign
1215          * @param string $skip Script body of the skip function
1216          * @return string
1217          */
1218         public static function makeLoaderRegisterScript( $name, $version = null,
1219                 $dependencies = null, $group = null, $source = null, $skip = null
1220         ) {
1221                 if ( is_array( $name ) ) {
1222                         return Xml::encodeJsCall(
1223                                 'mw.loader.register',
1224                                 array( $name ),
1225                                 ResourceLoader::inDebugMode()
1226                         );
1227                 } else {
1228                         $version = (int)$version > 1 ? (int)$version : 1;
1229                         return Xml::encodeJsCall(
1230                                 'mw.loader.register',
1231                                 array( $name, $version, $dependencies, $group, $source, $skip ),
1232                                 ResourceLoader::inDebugMode()
1233                         );
1234                 }
1235         }
1236
1237         /**
1238          * Returns JS code which calls mw.loader.addSource() with the given
1239          * parameters. Has two calling conventions:
1240          *
1241          *   - ResourceLoader::makeLoaderSourcesScript( $id, $properties ):
1242          *       Register a single source
1243          *
1244          *   - ResourceLoader::makeLoaderSourcesScript( array( $id1 => $loadUrl, $id2 => $loadUrl, ... ) );
1245          *       Register sources with the given IDs and properties.
1246          *
1247          * @param string $id Source ID
1248          * @param array $properties Source properties (see addSource())
1249          * @return string
1250          */
1251         public static function makeLoaderSourcesScript( $id, $properties = null ) {
1252                 if ( is_array( $id ) ) {
1253                         return Xml::encodeJsCall(
1254                                 'mw.loader.addSource',
1255                                 array( $id ),
1256                                 ResourceLoader::inDebugMode()
1257                         );
1258                 } else {
1259                         return Xml::encodeJsCall(
1260                                 'mw.loader.addSource',
1261                                 array( $id, $properties ),
1262                                 ResourceLoader::inDebugMode()
1263                         );
1264                 }
1265         }
1266
1267         /**
1268          * Returns JS code which runs given JS code if the client-side framework is
1269          * present.
1270          *
1271          * @param string $script JavaScript code
1272          * @return string
1273          */
1274         public static function makeLoaderConditionalScript( $script ) {
1275                 return "if(window.mw){\n" . trim( $script ) . "\n}";
1276         }
1277
1278         /**
1279          * Returns JS code which will set the MediaWiki configuration array to
1280          * the given value.
1281          *
1282          * @param array $configuration List of configuration values keyed by variable name
1283          * @return string
1284          */
1285         public static function makeConfigSetScript( array $configuration ) {
1286                 return Xml::encodeJsCall(
1287                         'mw.config.set',
1288                         array( $configuration ),
1289                         ResourceLoader::inDebugMode()
1290                 );
1291         }
1292
1293         /**
1294          * Convert an array of module names to a packed query string.
1295          *
1296          * For example, array( 'foo.bar', 'foo.baz', 'bar.baz', 'bar.quux' )
1297          * becomes 'foo.bar,baz|bar.baz,quux'
1298          * @param array $modules List of module names (strings)
1299          * @return string Packed query string
1300          */
1301         public static function makePackedModulesString( $modules ) {
1302                 $groups = array(); // array( prefix => array( suffixes ) )
1303                 foreach ( $modules as $module ) {
1304                         $pos = strrpos( $module, '.' );
1305                         $prefix = $pos === false ? '' : substr( $module, 0, $pos );
1306                         $suffix = $pos === false ? $module : substr( $module, $pos + 1 );
1307                         $groups[$prefix][] = $suffix;
1308                 }
1309
1310                 $arr = array();
1311                 foreach ( $groups as $prefix => $suffixes ) {
1312                         $p = $prefix === '' ? '' : $prefix . '.';
1313                         $arr[] = $p . implode( ',', $suffixes );
1314                 }
1315                 $str = implode( '|', $arr );
1316                 return $str;
1317         }
1318
1319         /**
1320          * Determine whether debug mode was requested
1321          * Order of priority is 1) request param, 2) cookie, 3) $wg setting
1322          * @return bool
1323          */
1324         public static function inDebugMode() {
1325                 if ( self::$debugMode === null ) {
1326                         global $wgRequest, $wgResourceLoaderDebug;
1327                         self::$debugMode = $wgRequest->getFuzzyBool( 'debug',
1328                                 $wgRequest->getCookie( 'resourceLoaderDebug', '', $wgResourceLoaderDebug )
1329                         );
1330                 }
1331                 return self::$debugMode;
1332         }
1333
1334         /**
1335          * Reset static members used for caching.
1336          *
1337          * Global state and $wgRequest are evil, but we're using it right
1338          * now and sometimes we need to be able to force ResourceLoader to
1339          * re-evaluate the context because it has changed (e.g. in the test suite).
1340          */
1341         public static function clearCache() {
1342                 self::$debugMode = null;
1343         }
1344
1345         /**
1346          * Build a load.php URL
1347          *
1348          * @since 1.24
1349          * @param string $source Name of the ResourceLoader source
1350          * @param ResourceLoaderContext $context
1351          * @param array $extraQuery
1352          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1353          */
1354         public function createLoaderURL( $source, ResourceLoaderContext $context,
1355                 $extraQuery = array()
1356         ) {
1357                 $query = self::createLoaderQuery( $context, $extraQuery );
1358                 $script = $this->getLoadScript( $source );
1359
1360                 // Prevent the IE6 extension check from being triggered (bug 28840)
1361                 // by appending a character that's invalid in Windows extensions ('*')
1362                 return wfExpandUrl( wfAppendQuery( $script, $query ) . '&*', PROTO_RELATIVE );
1363         }
1364
1365         /**
1366          * Build a load.php URL
1367          * @deprecated since 1.24, use createLoaderURL instead
1368          * @param array $modules Array of module names (strings)
1369          * @param string $lang Language code
1370          * @param string $skin Skin name
1371          * @param string|null $user User name. If null, the &user= parameter is omitted
1372          * @param string|null $version Versioning timestamp
1373          * @param bool $debug Whether the request should be in debug mode
1374          * @param string|null $only &only= parameter
1375          * @param bool $printable Printable mode
1376          * @param bool $handheld Handheld mode
1377          * @param array $extraQuery Extra query parameters to add
1378          * @return string URL to load.php. May be protocol-relative (if $wgLoadScript is procol-relative)
1379          */
1380         public static function makeLoaderURL( $modules, $lang, $skin, $user = null,
1381                 $version = null, $debug = false, $only = null, $printable = false,
1382                 $handheld = false, $extraQuery = array()
1383         ) {
1384                 global $wgLoadScript;
1385
1386                 $query = self::makeLoaderQuery( $modules, $lang, $skin, $user, $version, $debug,
1387                         $only, $printable, $handheld, $extraQuery
1388                 );
1389
1390                 // Prevent the IE6 extension check from being triggered (bug 28840)
1391                 // by appending a character that's invalid in Windows extensions ('*')
1392                 return wfExpandUrl( wfAppendQuery( $wgLoadScript, $query ) . '&*', PROTO_RELATIVE );
1393         }
1394
1395         /**
1396          * Helper for createLoaderURL()
1397          *
1398          * @since 1.24
1399          * @see makeLoaderQuery
1400          * @param ResourceLoaderContext $context
1401          * @param array $extraQuery
1402          * @return array
1403          */
1404         public static function createLoaderQuery( ResourceLoaderContext $context, $extraQuery = array() ) {
1405                 return self::makeLoaderQuery(
1406                         $context->getModules(),
1407                         $context->getLanguage(),
1408                         $context->getSkin(),
1409                         $context->getUser(),
1410                         $context->getVersion(),
1411                         $context->getDebug(),
1412                         $context->getOnly(),
1413                         $context->getRequest()->getBool( 'printable' ),
1414                         $context->getRequest()->getBool( 'handheld' ),
1415                         $extraQuery
1416                 );
1417         }
1418
1419         /**
1420          * Build a query array (array representation of query string) for load.php. Helper
1421          * function for makeLoaderURL().
1422          *
1423          * @param array $modules
1424          * @param string $lang
1425          * @param string $skin
1426          * @param string $user
1427          * @param string $version
1428          * @param bool $debug
1429          * @param string $only
1430          * @param bool $printable
1431          * @param bool $handheld
1432          * @param array $extraQuery
1433          *
1434          * @return array
1435          */
1436         public static function makeLoaderQuery( $modules, $lang, $skin, $user = null,
1437                 $version = null, $debug = false, $only = null, $printable = false,
1438                 $handheld = false, $extraQuery = array()
1439         ) {
1440                 $query = array(
1441                         'modules' => self::makePackedModulesString( $modules ),
1442                         'lang' => $lang,
1443                         'skin' => $skin,
1444                         'debug' => $debug ? 'true' : 'false',
1445                 );
1446                 if ( $user !== null ) {
1447                         $query['user'] = $user;
1448                 }
1449                 if ( $version !== null ) {
1450                         $query['version'] = $version;
1451                 }
1452                 if ( $only !== null ) {
1453                         $query['only'] = $only;
1454                 }
1455                 if ( $printable ) {
1456                         $query['printable'] = 1;
1457                 }
1458                 if ( $handheld ) {
1459                         $query['handheld'] = 1;
1460                 }
1461                 $query += $extraQuery;
1462
1463                 // Make queries uniform in order
1464                 ksort( $query );
1465                 return $query;
1466         }
1467
1468         /**
1469          * Check a module name for validity.
1470          *
1471          * Module names may not contain pipes (|), commas (,) or exclamation marks (!) and can be
1472          * at most 255 bytes.
1473          *
1474          * @param string $moduleName Module name to check
1475          * @return bool Whether $moduleName is a valid module name
1476          */
1477         public static function isValidModuleName( $moduleName ) {
1478                 return !preg_match( '/[|,!]/', $moduleName ) && strlen( $moduleName ) <= 255;
1479         }
1480
1481         /**
1482          * Returns LESS compiler set up for use with MediaWiki
1483          *
1484          * @param Config $config
1485          * @throws MWException
1486          * @since 1.22
1487          * @return lessc
1488          */
1489         public static function getLessCompiler( Config $config ) {
1490                 // When called from the installer, it is possible that a required PHP extension
1491                 // is missing (at least for now; see bug 47564). If this is the case, throw an
1492                 // exception (caught by the installer) to prevent a fatal error later on.
1493                 if ( !function_exists( 'ctype_digit' ) ) {
1494                         throw new MWException( 'lessc requires the Ctype extension' );
1495                 }
1496
1497                 $less = new lessc();
1498                 $less->setPreserveComments( true );
1499                 $less->setVariables( self::getLessVars( $config ) );
1500                 $less->setImportDir( $config->get( 'ResourceLoaderLESSImportPaths' ) );
1501                 foreach ( $config->get( 'ResourceLoaderLESSFunctions' ) as $name => $func ) {
1502                         $less->registerFunction( $name, $func );
1503                 }
1504                 return $less;
1505         }
1506
1507         /**
1508          * Get global LESS variables.
1509          *
1510          * @param Config $config
1511          * @since 1.22
1512          * @return array Map of variable names to string CSS values.
1513          */
1514         public static function getLessVars( Config $config ) {
1515                 $lessVars = $config->get( 'ResourceLoaderLESSVars' );
1516                 // Sort by key to ensure consistent hashing for cache lookups.
1517                 ksort( $lessVars );
1518                 return $lessVars;
1519         }
1520 }